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BACKGROUND: Early diagnosis of autism spectrum disorder (ASD) is essential in most Canadian jurisdictions to access interventions that improve long-term child outcomes. Our main objective was to identify factors associated with timing of ASD diagnosis in five provinces across Canada. METHODS: Factors influencing age of diagnosis were assessed in the analyses of an inception cohort of children diagnosed with ASD between ages 2 and 5 years. We examined bivariate associations and using a series of multiple variable regression models, evaluated the unique contributions of developmental functioning, ASD symptoms and demographic variables. Children with known genetic abnormalities, or severe sensory or motor impairments interfering with assessment were excluded. RESULTS: Participants were 421 children (84.6% boys). The mean age of diagnosis was 38.2 months (SD=8.7), an average of 19 months after parents identified initial concerns. Factors associated with later diagnosis included more advanced language and cognitive skills, and higher levels of restricted repetitive behaviour symptoms. Child sex and family demographics were not associated with age of diagnosis. In regression analyses, language and cognitive skills accounted for 6.8% of variance in age of diagnosis and ASD symptoms contributed an additional 5.5%. Provincial site accounted for 4.0% of variance in age of diagnosis, independent of developmental skills and ASD symptoms. INTERPRETATION: Diagnosis of ASD occurred, on average, 19 months after parents’ initial concerns. Language and cognitive skills, symptom severity and provincial site accounted for variation in age of ASD diagnosis in this Canadian cohort. Variable presentation across the developmental continuum must be considered in planning assessment services to ensure timely ASD diagnosis so that outcomes can be improved. Policy and practice leadership is also needed to reduce interprovincial variability.

Background The clinical integration of chromosomal microarray testing promises improvements in diagnostic yields in Autism Spectrum Disorder (ASD). While the impact on clinical management is promising for some families, the utility perceived by families, including the majority for whom results are negative, is unclear. With next generation genomic sequencing technologies poised for integration, along with promising ASD biomarkers being developed, there is a need to understand the extent to which genomic and other biological testing would have utility for the target recipients of these tests and their families. The purpose of the present cross-sectional study was to examine the predictors of perceived utility of biological testing among parents of a child with ASD. Methods The Perceived Utility of Biotesting (PUB) Questionnaire was developed based on literature review and integrating family review. Following their child’s diagnosis, families participating in an ongoing prospective study completed the PUB questionnaire along with self-reported measures of parent stress, child and family functioning, and family-centered care prior to undergoing genetic testing for both clinical and research purposes. Results Based on n = 85 families, psychometric properties of the Perceived Utility of Biotesting questionnaire suggest a reliable and valid instrument. A stepwise regression analysis reveals that lower levels of child emotional and behavioural functioning and higher levels of family functioning correlated with higher perceived utility for biological testing. Limitations A main limitation in the study is the participation rate of 50 %, thus the possibility of self-selection bias cannot be ruled out. We also chose to assess perceived utility among parents rather than the individuals with ASD themselves: modifying the questionnaire to capture perceived utility from autistic individuals across the lifespan would prove essential in future studies. Finally, ongoing validation of the PUB by assessing the PUB’s discriminant and convergent validity is still needed. Conclusions We conclude that the utility of biological testing perceived by families whose child is undergoing genetic testing around ASD diagnosis depends on their unique child and family characteristics. This signifies that engaging families in biomarker discovery for improving the impact of research and care requires systematic input from a representative sample of families.

Understanding the overall utility of biological testing for autism spectrum disorder (ASD) is essential for the development and integration of biomarkers into routine care. One measure related to the overall utility of biological testing is the knowledge that a person has about the condition he/she suffers from. However, a major gap towards understanding the role of knowledge in overall utility is the absence of studies that have assessed knowledge of autism along with its predictors within a representative sample of families within the context of routine care. The objective of this study was to measure knowledge of ASD among families within the routine care pathway for biological testing in ASD by examining the association between knowledge with potential correlates of knowledge namely sociodemographic factors, parental stress and distress, and time since diagnosis among parents whose child with ASD is undergoing clinical genetic testing. Parents of a child diagnosed with ASD (n = 85, Mage = 39.0, SD = 7.7) participating in an ongoing prospective genomics study completed the ASD Quiz prior to undergoing genetic testing for clinical and research purposes. Parents also completed self-reported measures of stress and distress. Parent stress and distress was each independently correlated with knowledge of ASD, rs ≥ 0.26, ps < 0.05. Stepwise regression analysis revealed a significant model accounting for 7.8% of the variance in knowledge, F (1, 82) = 8.02, p = 0.006. The only factor significantly associated with knowledge was parental distress, β = 0.30, p = 0.006. Parental stress, time since diagnosis, and sociodemographic factors were not significant predictors in this model. We concluded that families require tailored support prior to undergoing genetic testing to address either knowledge gaps or high distress. Ongoing appraisal of the testing process among families of diverse backgrounds is essential in offering optimal care for families undergoing genetic testing.

In order to conduct the screening phase of the first epidemiological survey of autism spectrum disorders (ASDs) in Mexico, we needed a screening tool to detect autistic symptomatology in a large sample of school-age children. We used the Spanish version of the Social Responsiveness Scale (SRS). We recruited a clinical sample of 200 children (81% males; mean age: 7.4 years) with a confirmed diagnosis of ASDs and a sample of 363 control children (59.5% males; mean age: 8.5 years) without ASDs. Three-way analyses of variance (ANOVAs) identified a main effect of clinical status (ASDs vs. controls) for both parent and teacher scales, but no gender or age effect. The mean total and subscale raw scores were significantly different between the clinical and control groups for the parent and for the teacher SRS (P < 0.001). The internal consistency of the SRS was excellent. Receiver operating characteristic (ROC) analyses showed excellent discriminant validity of the SRS in the Mexican sample (area under the curve: 0.962 for the parent, 0.960 for the teacher). ROC curves were also used to determine which cutoff would provide the best trade-off between sensitivity and specificity. Mexican SRS scores were significantly higher than in the U.S. and German population for typically developing children but comparable for clinically referred subjects. The SRS is an acceptable screening instrument for epidemiological studies of ASDs in Mexico. Its psychometric properties are excellent and comparable to those derived from North American and other samples.

There are no epidemiological data on autism for Mexico. This study was conducted to generate a first estimate of ASD prevalence in Mexico. We surveyed children age eight in Leon (Guanajuato). The sample was stratified in two strata: (1) children having special education and medical records (SEMR; N = 432) and (2) children attending regular schools (GSS; N = 11,684). GSS children were screened with the SRS and those with the highest scores were invited to a diagnostic evaluation. The final sample comprised 36 children (80.6 % male) who had confirmed ASD. A third had intellectual disability, 25 % were non-verbal, 69 % had co-occurring behavioral problems. The prevalence overall was 0.87 % (95 % CI 0.62, 1.1 %). This survey provides an estimate for ASD prevalence in Mexico that is consistent with recent studies.